Despite its recent surge in popularity, fasting is a practice that dates back centuries and plays a central role in many cultures and religions. Defined as the abstinence from all or some foods or drinks for a set period of time, there are many different ways of fasting. In general, most types of fasts are performed over 24–72 hours. Intermittent fasting, on the other hand, involves cycling between periods of eating and fasting, ranging from a few hours to a few days at a time.
Fasting has been shown to have many health benefits, from increased weight loss to better brain function and improved gut health.
Promotes Blood Sugar Control by Reducing Insulin Resistance
Several studies have found that fasting may improve blood sugar control, which could be especially useful for those at risk of diabetes. In fact, one study in 10 people with type 2 diabetes showed that short-term intermittent fasting significantly decreased blood sugar levels.
Promotes Better Health by Fighting Inflammation
While acute inflammation is a normal immune process used to help fight off infections, chronic inflammation can have serious consequences for your health. Research shows that inflammation may be involved in the development of chronic conditions, such as heart disease, cancer and rheumatoid arthritis. Some studies have found that fasting can help decreases level of infalmation and help promote better health.
May Enhance Heart Health by Improving Blood Pressure, Triglycerides and Cholesterol Levels
Some research has found that incorporating fasting into your routine may be especially beneficial when it comes to heart health. One small study revealed that eight weeks of alternate-day fasting reduced levels of “bad” LDL cholesterol and blood triglycerides by 25% and 32% respectively.
May Boost Brain Function and Prevent Neurodegenerative Disorders
Though research is mostly limited to animal research, several studies have found that fasting could have a powerful effect on brain health. One study in mice showed that practicing intermittent fasting for 11 months improved both brain function and brain structure .
Because fasting may also help relieve inflammation, it could also aid in preventing neurodegenerative disorders. In particular, studies in animals suggest that fasting may protect against and improve outcomes for conditions such as Alzheimer’s disease and Parkinson’s. However, more studies are needed to evaluate the effects of fasting on brain function in humans.
Aids Weight Loss by Limiting Calorie Intake and Boosting Metabolism
Some research has also found that short-term fasting may boost metabolism by increasing levels of the neurotransmitter nor epinephrine, which could enhance weight loss .In fact, one review showed that whole-day fasting could reduce body weight by up to 9% and significantly decrease body fat over 12–24 weeks .
Another review found that intermittent fasting over 3–12 weeks was as effective in inducing weight loss as continuous calorie restriction and decreased body weight and fat mass by up to 8% and 16% respectively .
Increases Growth Hormone Secretion, Which Is Vital for Growth, Metabolism, Weight Loss and Muscle Strength
Human growth hormone (HGH) is a type of protein hormone that is central to many aspects of your health. In fact, research shows that this key hormone is involved in growth, metabolism, and weight loss and muscle strength. Several studies have found that fasting could naturally increase HGH.
Could Delay Aging and Extend Longevity
Several animal studies have found promising results on the potential lifespan-extending effects of fasting. Fasting could be effective in increasing longevity and survival rates.
However, current research is still limited to animal studies. Further studies are needed to understand how fasting may impact longevity and aging in humans.
May Aid in Cancer Prevention and Increase the Effectiveness of Chemotherapy
Animal and test-tube studies indicate that fasting may benefit the treatment and prevention of cancer. In fact, one rat study found that alternate-day fasting helped block tumour formation.
How to Start Fasting
There are many different types of fasts, making it easy to find a method that fits your lifestyle. Here are a few of the most common types of fasting:
Water fasting: Involves drinking only water for a set amount of time.
Juice fasting: Entails only drinking vegetable or fruit juice for a certain period.
Intermittent fasting: Intake is partially or completely restricted for a few hours up to a few days at a time and a normal diet is resumed on other days.
Partial fasting: Certain foods or drinks such as processed foods, animal products or caffeine are eliminated from the diet for a set period.
Calorie restriction: Calories are restricted for a few days every week.
Within these categories are also more specific types of fasts.
For example, intermittent fasting can be broken down into subcategories such as alternate-day fasting, which involves eating every other day, or time-restricted feeding, which entails limiting intake to just a few hours each day. To get started, try experimenting with different types of fasting to find what works best for you.
Safety and Side Effects
Despite the long list of possible health benefits associated with fasting, it may not be right for everyone. If you suffer from diabetes or low blood sugar, fasting can lead to spikes and crashes in your blood sugar levels, which could be dangerous.
It’s best to talk to your doctor first if you have any underlying health conditions or are planning to fast for more than 24 hours. Additionally, fasting is not generally recommended without medical supervision for older adults, adolescents or people who are underweight.
If you decide to try fasting, be sure to stay well-hydrated and fill your diet with nutrient-dense foods during your eating periods to maximize the potential health benefits. Additionally, if fasting for longer periods, try to minimize intense physical activity and get plenty of rest.
The Bottom Line
Fasting is a practice that has been associated with a wide array of potential health benefits, including weight loss, as well as improved blood sugar control, heart health, brain function and cancer prevention.
From water fasting to intermittent fasting and calorie restriction, there are many different types of fasting that fit nearly every lifestyle.
When coupled with a nutritious diet and healthy lifestyle incorporating fasting into your routine could benefit your health.